The present disclosure relates to an in-vehicle communication system, and relates to, for example, an in-vehicle communication system mounted on a vehicle. Further, the present disclosure relates to a domain master and a firmware update method, and relates to, for example, a domain master used for an in-vehicle communication system, and a firmware update method of the domain master.
Japanese Unexamined Patent Application Publication No. 2008-259124 discloses an in-vehicle communication system. The in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124 includes a plurality of electronic control units (ECUs) and a communication data relay apparatus. In the in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124, the plurality of ECUs are divided into groups for each functional group such as a power train system, a chassis system, a body system, and an Advanced Driving Assistant System (ADAS), and ECUs that belong to one group (one domain) are configured to be able to communicate with one another via a bus provided for each functional group.
In the in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124, a communication data mediation apparatus is arranged between buses whose functional groups are different from each other, and relays communication between different domains. In the in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124, data can be shared among different functional groups by using the communication data mediation apparatus.
In the in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124, the ECU that connects the buses whose functional groups are different from each other includes abnormality detection means for detecting an abnormality of the communication data mediation apparatus. The ECU further includes taking-over means for taking over the functions of the communication data mediation apparatus when an abnormality of the communication data mediation apparatus has been detected. In the in-vehicle communication system disclosed in Japanese Unexamined Patent Application Publication No. 2008-259124, even when there is an abnormality in the communication data mediation apparatus, the ECU that connects the buses whose functional groups are different from each other serves as the communication data mediation apparatus, whereby data sharing among different functional groups is continued.
In recent years, in accordance with an increase in the amount of data communicated on a vehicle network system, an in-vehicle communication system may be configured to include a domain master (hereinafter this may be also referred to as a DM) that aggregates communication networks in functional domains such as a controller area network (CAN) for each functional group of the vehicle and a gateway (hereinafter this may be also referred to as a GW) that aggregates high-speed communication networks that connect the functional domains. When reprogramming of an embedded control program (firmware) of the DM is performed in this network configuration, data necessary for the reprogramming is delivered to the DM from the GW via the high-speed communication network, and the reprogramming of the embedded control program is executed in the DM.
While the aforementioned reprogramming of the embedded control program of the DM is being performed, the function of the DM is stopped. When the reprogramming of the embedded control program of the DM is executed while the vehicle is being stopped, various types of control do not need to be executed in the functional domains. Therefore, no problem occurs even when the DM stops its functions during the reprogramming.
In recent years, because of the achievement of Firmware On-The-Air (FOTA), it might seem like it would be possible to execute reprogramming of the embedded control program of the DM not only while the vehicle is not travelling, but also while the vehicle is travelling. However, while the vehicle is travelling, various types of control need to be executed in the functional domains, and the functions of the DM cannot be stopped. Therefore, it is impossible to execute reprogramming of the embedded control program of the DM while the vehicle is travelling.
Japanese Unexamined Patent Application Publication No. 2008-259124 merely discloses detecting an abnormality of the communication data mediation apparatus and taking over, by the ECU, the functions of the communication data mediation apparatus. Accordingly, Japanese Unexamined Patent Application Publication No. 2008-259124 does not provide technical means for allowing the embedded control program of the DM to be updated while the vehicle is travelling.
The other problems and the novel characteristics will be made apparent from the descriptions of this specification and the attached drawings.